Quantum creep in Y1-xPrxBa2Cu3O7-delta crystals: Magnetic relaxation and transport

Citation
T. Stein et al., Quantum creep in Y1-xPrxBa2Cu3O7-delta crystals: Magnetic relaxation and transport, PHYS REV L, 82(14), 1999, pp. 2955-2958
Citations number
16
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW LETTERS
ISSN journal
00319007 → ACNP
Volume
82
Issue
14
Year of publication
1999
Pages
2955 - 2958
Database
ISI
SICI code
0031-9007(19990405)82:14<2955:QCIYCM>2.0.ZU;2-5
Abstract
We report transport and magnetic relaxation measurements in the mixed state of strongly underdoped Y1-xPrxBa2CU3O7-delta crystals. A transition from t hermally activated flux creep to temperature-independent quantum flux creep is observed in both transport and magnetic relaxation at temperatures T le ss than or equal to 5 K. Flux transformer measurements indicate that the cr ossover to quantum creep is preceded by a coupling transition. Based on the se observations we argue that below the coupling transition the current is confined within a very narrow layer beneath the current contacts. [S0031-90 07(99)08855-9].